1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  S390 version
4  *    Copyright IBM Corp. 1999
5  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
6  *
7  *  Derived from "include/asm-i386/current.h"
8  */
9 
10 #ifndef _S390_CURRENT_H
11 #define _S390_CURRENT_H
12 
13 #include <asm/lowcore.h>
14 #include <asm/machine.h>
15 
16 struct task_struct;
17 
18 static __always_inline struct task_struct *get_current(void)
19 {
20 	unsigned long ptr, lc_current;
21 
22 	lc_current = offsetof(struct lowcore, current_task);
23 	asm_inline(
24 		ALTERNATIVE("	lg	%[ptr],%[offzero](%%r0)\n",
25 			    "	lg	%[ptr],%[offalt](%%r0)\n",
26 			    ALT_FEATURE(MFEATURE_LOWCORE))
27 		: [ptr] "=d" (ptr)
28 		: [offzero] "i" (lc_current),
29 		  [offalt] "i" (lc_current + LOWCORE_ALT_ADDRESS));
30 	return (struct task_struct *)ptr;
31 }
32 
33 #define current get_current()
34 
35 #endif /* !(_S390_CURRENT_H) */
36